Why election experts worry for American democracy and what they say can be done

Donald Trump first introduced unsubstantiated election fraud conspiracy claims into the political mainstream during the 2016 campaign before making them the focus of his final months in the White House and the two years since, inspiring a slew of candidates and supporters who believe the same.

It's an alarming trend, according to some election experts and historians who warn, if left unabated, it could weaken -- or in the extreme -- dismantle American democracy.

The ABC News series "Democracy in Peril," which rolls out this week, is examining questions and concerns about America's democratic institutions at all levels in the wake of Jan. 6. The riot at the Capitol exemplified, some experts say, how extreme election denial has been on the rise, especially among Republicans -- and can be intertwined with violence. And the constant drumbeat of denialism, these experts say, is eroding the very foundation of trust that democratic institutions rely on to function.

"For the election system to work, our entire democracy to work, depends on trust in the election system. That is the reason why there is and has always been a peaceful transition of power after elections in the United States," said Wendy Weiser, who directs the Democracy Program at the Brennan Center for Justice. "And if that belief isn't there, then there's a real risk that can see more resistance to peaceful transitions of power, more resistance to the electoral system overall."

Sporadic and groundless claims of widespread election fraud have been made since the country's founding, but in modern times they have never been made more consistently -- and now, polling suggests a full third of the electorate thinks the Biden's victory was illegitimate. Much of it is tied to Trump, experts say, after he made the fraud claims a litmus test for GOP candidates and the heart of his platform.

Experts note such claims weren't made after two close presidential elections in 1960 and 2000, which were each controversial and could have been contested, and while some Democrats did object to the presidential results in Ohio in 2004, that effort was shut down in two bipartisan votes. And while there have been decades-long disputes over how relaxed or restrictive voting should be -- flaring during the civil rights movement, for example -- experts say the lack of faith in today's elections and state legislatures' efforts to clamp down on access to the ballot is unique.

"There's nothing that even remotely compares to what we're going through right now," presidential historian Mark Updegrove told ABC News.

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